Certain lines for treating metal strips include a station for covering the strip continuously with a coating of the varnish type; and on leaving the station, the strip passes through a dryer in which its temperature may be raised to more than 220.degree. C. Downstream from this section of the treatment line, the strip is cooled. The length of strip required for cooling purposes is so long that the strip must follow a path which includes loops, and therefore which includes devices for deflecting the strip. Such deflection is generally provided by a metal roller of sufficiently large diameter and around which the strip is wound through 90.degree. or more. Further devices of this type occur along the path of the strip within the treatment line.
It is observed that on leaving the drying station, the product is ill-suited for bending since the coating is fragile. As the strip winds round a roller the coating flakes off in places, and blisters also occur in places on the coated sheet.
The present invention seeks to remedy these manufacturing defects by providing a deflection device which does not damage the coating on making with contact with the strip.